The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Generally, a powertrain that transmits power from an engine and a motor to a transmission through a dry clutch has a connection structure including an engine, engine clutch, motor, dry clutch, and transmission, in which the transmission may be an automated manual transmission (AMT) or a dual clutch transmission (DCT). FIG. 1 shows an example of a powertrain using a DCT.
For reference, the dry clutch between the motor and the transmission is considered to be a component of an AMT or a DCT in some cases, but is assumed here to be a separate component, as exemplified in FIG. 1.
The dry clutch (hereafter, briefly referred to as a ‘clutch’) has clutch transfer torque that is greatly changed in accordance with many factors such as the degree of friction due to single tolerance and durability of the components of a clutch, thermal deformation by high temperature, and changes in friction coefficient, so it is difficult to precisely determine the transfer torque that is the torque transmitted by a clutch while a vehicle is running.
However, if a change in transfer torque is not known while a clutch in a vehicle is controlled, the clutch may slip excessively or may cause a shock when engaging, so there is a need for estimating and correcting the transfer torque characteristics of a clutch in real time.
In particular, in a Hybrid Electric Vehicle (HEV) powertrain that transmits power from both an engine and a motor to a clutch, unlike the way a clutch typically transmits only engine torque to a transmission, it is desirable to estimate and correct transfer torque of a clutch in consideration of the influence on the clutch of the motor torque.
The description provided above as a related art of the present disclosure is just for helping understanding the background of the present disclosure and should not be construed as being included in the related art known by those skilled in the art.
Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.